xref: /openbmc/linux/drivers/hwmon/fam15h_power.c (revision 4419617e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * fam15h_power.c - AMD Family 15h processor power monitoring
4  *
5  * Copyright (c) 2011-2016 Advanced Micro Devices, Inc.
6  * Author: Andreas Herrmann <herrmann.der.user@googlemail.com>
7  */
8 
9 #include <linux/err.h>
10 #include <linux/hwmon.h>
11 #include <linux/hwmon-sysfs.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/pci.h>
15 #include <linux/bitops.h>
16 #include <linux/cpu.h>
17 #include <linux/cpumask.h>
18 #include <linux/time.h>
19 #include <linux/sched.h>
20 #include <asm/processor.h>
21 #include <asm/msr.h>
22 
23 MODULE_DESCRIPTION("AMD Family 15h CPU processor power monitor");
24 MODULE_AUTHOR("Andreas Herrmann <herrmann.der.user@googlemail.com>");
25 MODULE_LICENSE("GPL");
26 
27 /* D18F3 */
28 #define REG_NORTHBRIDGE_CAP		0xe8
29 
30 /* D18F4 */
31 #define REG_PROCESSOR_TDP		0x1b8
32 
33 /* D18F5 */
34 #define REG_TDP_RUNNING_AVERAGE		0xe0
35 #define REG_TDP_LIMIT3			0xe8
36 
37 #define FAM15H_MIN_NUM_ATTRS		2
38 #define FAM15H_NUM_GROUPS		2
39 #define MAX_CUS				8
40 
41 /* set maximum interval as 1 second */
42 #define MAX_INTERVAL			1000
43 
44 #define MSR_F15H_CU_PWR_ACCUMULATOR	0xc001007a
45 #define MSR_F15H_CU_MAX_PWR_ACCUMULATOR	0xc001007b
46 #define MSR_F15H_PTSC			0xc0010280
47 
48 #define PCI_DEVICE_ID_AMD_15H_M70H_NB_F4 0x15b4
49 
50 struct fam15h_power_data {
51 	struct pci_dev *pdev;
52 	unsigned int tdp_to_watts;
53 	unsigned int base_tdp;
54 	unsigned int processor_pwr_watts;
55 	unsigned int cpu_pwr_sample_ratio;
56 	const struct attribute_group *groups[FAM15H_NUM_GROUPS];
57 	struct attribute_group group;
58 	/* maximum accumulated power of a compute unit */
59 	u64 max_cu_acc_power;
60 	/* accumulated power of the compute units */
61 	u64 cu_acc_power[MAX_CUS];
62 	/* performance timestamp counter */
63 	u64 cpu_sw_pwr_ptsc[MAX_CUS];
64 	/* online/offline status of current compute unit */
65 	int cu_on[MAX_CUS];
66 	unsigned long power_period;
67 };
68 
69 static bool is_carrizo_or_later(void)
70 {
71 	return boot_cpu_data.x86 == 0x15 && boot_cpu_data.x86_model >= 0x60;
72 }
73 
74 static ssize_t power1_input_show(struct device *dev,
75 				 struct device_attribute *attr, char *buf)
76 {
77 	u32 val, tdp_limit, running_avg_range;
78 	s32 running_avg_capture;
79 	u64 curr_pwr_watts;
80 	struct fam15h_power_data *data = dev_get_drvdata(dev);
81 	struct pci_dev *f4 = data->pdev;
82 
83 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
84 				  REG_TDP_RUNNING_AVERAGE, &val);
85 
86 	/*
87 	 * On Carrizo and later platforms, TdpRunAvgAccCap bit field
88 	 * is extended to 4:31 from 4:25.
89 	 */
90 	if (is_carrizo_or_later()) {
91 		running_avg_capture = val >> 4;
92 		running_avg_capture = sign_extend32(running_avg_capture, 27);
93 	} else {
94 		running_avg_capture = (val >> 4) & 0x3fffff;
95 		running_avg_capture = sign_extend32(running_avg_capture, 21);
96 	}
97 
98 	running_avg_range = (val & 0xf) + 1;
99 
100 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
101 				  REG_TDP_LIMIT3, &val);
102 
103 	/*
104 	 * On Carrizo and later platforms, ApmTdpLimit bit field
105 	 * is extended to 16:31 from 16:28.
106 	 */
107 	if (is_carrizo_or_later())
108 		tdp_limit = val >> 16;
109 	else
110 		tdp_limit = (val >> 16) & 0x1fff;
111 
112 	curr_pwr_watts = ((u64)(tdp_limit +
113 				data->base_tdp)) << running_avg_range;
114 	curr_pwr_watts -= running_avg_capture;
115 	curr_pwr_watts *= data->tdp_to_watts;
116 
117 	/*
118 	 * Convert to microWatt
119 	 *
120 	 * power is in Watt provided as fixed point integer with
121 	 * scaling factor 1/(2^16).  For conversion we use
122 	 * (10^6)/(2^16) = 15625/(2^10)
123 	 */
124 	curr_pwr_watts = (curr_pwr_watts * 15625) >> (10 + running_avg_range);
125 	return sprintf(buf, "%u\n", (unsigned int) curr_pwr_watts);
126 }
127 static DEVICE_ATTR_RO(power1_input);
128 
129 static ssize_t power1_crit_show(struct device *dev,
130 				struct device_attribute *attr, char *buf)
131 {
132 	struct fam15h_power_data *data = dev_get_drvdata(dev);
133 
134 	return sprintf(buf, "%u\n", data->processor_pwr_watts);
135 }
136 static DEVICE_ATTR_RO(power1_crit);
137 
138 static void do_read_registers_on_cu(void *_data)
139 {
140 	struct fam15h_power_data *data = _data;
141 	int cpu, cu;
142 
143 	cpu = smp_processor_id();
144 
145 	/*
146 	 * With the new x86 topology modelling, cpu core id actually
147 	 * is compute unit id.
148 	 */
149 	cu = cpu_data(cpu).cpu_core_id;
150 
151 	rdmsrl_safe(MSR_F15H_CU_PWR_ACCUMULATOR, &data->cu_acc_power[cu]);
152 	rdmsrl_safe(MSR_F15H_PTSC, &data->cpu_sw_pwr_ptsc[cu]);
153 
154 	data->cu_on[cu] = 1;
155 }
156 
157 /*
158  * This function is only able to be called when CPUID
159  * Fn8000_0007:EDX[12] is set.
160  */
161 static int read_registers(struct fam15h_power_data *data)
162 {
163 	int core, this_core;
164 	cpumask_var_t mask;
165 	int ret, cpu;
166 
167 	ret = zalloc_cpumask_var(&mask, GFP_KERNEL);
168 	if (!ret)
169 		return -ENOMEM;
170 
171 	memset(data->cu_on, 0, sizeof(int) * MAX_CUS);
172 
173 	get_online_cpus();
174 
175 	/*
176 	 * Choose the first online core of each compute unit, and then
177 	 * read their MSR value of power and ptsc in a single IPI,
178 	 * because the MSR value of CPU core represent the compute
179 	 * unit's.
180 	 */
181 	core = -1;
182 
183 	for_each_online_cpu(cpu) {
184 		this_core = topology_core_id(cpu);
185 
186 		if (this_core == core)
187 			continue;
188 
189 		core = this_core;
190 
191 		/* get any CPU on this compute unit */
192 		cpumask_set_cpu(cpumask_any(topology_sibling_cpumask(cpu)), mask);
193 	}
194 
195 	on_each_cpu_mask(mask, do_read_registers_on_cu, data, true);
196 
197 	put_online_cpus();
198 	free_cpumask_var(mask);
199 
200 	return 0;
201 }
202 
203 static ssize_t power1_average_show(struct device *dev,
204 				   struct device_attribute *attr, char *buf)
205 {
206 	struct fam15h_power_data *data = dev_get_drvdata(dev);
207 	u64 prev_cu_acc_power[MAX_CUS], prev_ptsc[MAX_CUS],
208 	    jdelta[MAX_CUS];
209 	u64 tdelta, avg_acc;
210 	int cu, cu_num, ret;
211 	signed long leftover;
212 
213 	/*
214 	 * With the new x86 topology modelling, x86_max_cores is the
215 	 * compute unit number.
216 	 */
217 	cu_num = boot_cpu_data.x86_max_cores;
218 
219 	ret = read_registers(data);
220 	if (ret)
221 		return 0;
222 
223 	for (cu = 0; cu < cu_num; cu++) {
224 		prev_cu_acc_power[cu] = data->cu_acc_power[cu];
225 		prev_ptsc[cu] = data->cpu_sw_pwr_ptsc[cu];
226 	}
227 
228 	leftover = schedule_timeout_interruptible(msecs_to_jiffies(data->power_period));
229 	if (leftover)
230 		return 0;
231 
232 	ret = read_registers(data);
233 	if (ret)
234 		return 0;
235 
236 	for (cu = 0, avg_acc = 0; cu < cu_num; cu++) {
237 		/* check if current compute unit is online */
238 		if (data->cu_on[cu] == 0)
239 			continue;
240 
241 		if (data->cu_acc_power[cu] < prev_cu_acc_power[cu]) {
242 			jdelta[cu] = data->max_cu_acc_power + data->cu_acc_power[cu];
243 			jdelta[cu] -= prev_cu_acc_power[cu];
244 		} else {
245 			jdelta[cu] = data->cu_acc_power[cu] - prev_cu_acc_power[cu];
246 		}
247 		tdelta = data->cpu_sw_pwr_ptsc[cu] - prev_ptsc[cu];
248 		jdelta[cu] *= data->cpu_pwr_sample_ratio * 1000;
249 		do_div(jdelta[cu], tdelta);
250 
251 		/* the unit is microWatt */
252 		avg_acc += jdelta[cu];
253 	}
254 
255 	return sprintf(buf, "%llu\n", (unsigned long long)avg_acc);
256 }
257 static DEVICE_ATTR_RO(power1_average);
258 
259 static ssize_t power1_average_interval_show(struct device *dev,
260 					    struct device_attribute *attr,
261 					    char *buf)
262 {
263 	struct fam15h_power_data *data = dev_get_drvdata(dev);
264 
265 	return sprintf(buf, "%lu\n", data->power_period);
266 }
267 
268 static ssize_t power1_average_interval_store(struct device *dev,
269 					     struct device_attribute *attr,
270 					     const char *buf, size_t count)
271 {
272 	struct fam15h_power_data *data = dev_get_drvdata(dev);
273 	unsigned long temp;
274 	int ret;
275 
276 	ret = kstrtoul(buf, 10, &temp);
277 	if (ret)
278 		return ret;
279 
280 	if (temp > MAX_INTERVAL)
281 		return -EINVAL;
282 
283 	/* the interval value should be greater than 0 */
284 	if (temp <= 0)
285 		return -EINVAL;
286 
287 	data->power_period = temp;
288 
289 	return count;
290 }
291 static DEVICE_ATTR_RW(power1_average_interval);
292 
293 static int fam15h_power_init_attrs(struct pci_dev *pdev,
294 				   struct fam15h_power_data *data)
295 {
296 	int n = FAM15H_MIN_NUM_ATTRS;
297 	struct attribute **fam15h_power_attrs;
298 	struct cpuinfo_x86 *c = &boot_cpu_data;
299 
300 	if (c->x86 == 0x15 &&
301 	    (c->x86_model <= 0xf ||
302 	     (c->x86_model >= 0x60 && c->x86_model <= 0x7f)))
303 		n += 1;
304 
305 	/* check if processor supports accumulated power */
306 	if (boot_cpu_has(X86_FEATURE_ACC_POWER))
307 		n += 2;
308 
309 	fam15h_power_attrs = devm_kcalloc(&pdev->dev, n,
310 					  sizeof(*fam15h_power_attrs),
311 					  GFP_KERNEL);
312 
313 	if (!fam15h_power_attrs)
314 		return -ENOMEM;
315 
316 	n = 0;
317 	fam15h_power_attrs[n++] = &dev_attr_power1_crit.attr;
318 	if (c->x86 == 0x15 &&
319 	    (c->x86_model <= 0xf ||
320 	     (c->x86_model >= 0x60 && c->x86_model <= 0x7f)))
321 		fam15h_power_attrs[n++] = &dev_attr_power1_input.attr;
322 
323 	if (boot_cpu_has(X86_FEATURE_ACC_POWER)) {
324 		fam15h_power_attrs[n++] = &dev_attr_power1_average.attr;
325 		fam15h_power_attrs[n++] = &dev_attr_power1_average_interval.attr;
326 	}
327 
328 	data->group.attrs = fam15h_power_attrs;
329 
330 	return 0;
331 }
332 
333 static bool should_load_on_this_node(struct pci_dev *f4)
334 {
335 	u32 val;
336 
337 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 3),
338 				  REG_NORTHBRIDGE_CAP, &val);
339 	if ((val & BIT(29)) && ((val >> 30) & 3))
340 		return false;
341 
342 	return true;
343 }
344 
345 /*
346  * Newer BKDG versions have an updated recommendation on how to properly
347  * initialize the running average range (was: 0xE, now: 0x9). This avoids
348  * counter saturations resulting in bogus power readings.
349  * We correct this value ourselves to cope with older BIOSes.
350  */
351 static const struct pci_device_id affected_device[] = {
352 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
353 	{ 0 }
354 };
355 
356 static void tweak_runavg_range(struct pci_dev *pdev)
357 {
358 	u32 val;
359 
360 	/*
361 	 * let this quirk apply only to the current version of the
362 	 * northbridge, since future versions may change the behavior
363 	 */
364 	if (!pci_match_id(affected_device, pdev))
365 		return;
366 
367 	pci_bus_read_config_dword(pdev->bus,
368 		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
369 		REG_TDP_RUNNING_AVERAGE, &val);
370 	if ((val & 0xf) != 0xe)
371 		return;
372 
373 	val &= ~0xf;
374 	val |=  0x9;
375 	pci_bus_write_config_dword(pdev->bus,
376 		PCI_DEVFN(PCI_SLOT(pdev->devfn), 5),
377 		REG_TDP_RUNNING_AVERAGE, val);
378 }
379 
380 #ifdef CONFIG_PM
381 static int fam15h_power_resume(struct pci_dev *pdev)
382 {
383 	tweak_runavg_range(pdev);
384 	return 0;
385 }
386 #else
387 #define fam15h_power_resume NULL
388 #endif
389 
390 static int fam15h_power_init_data(struct pci_dev *f4,
391 				  struct fam15h_power_data *data)
392 {
393 	u32 val;
394 	u64 tmp;
395 	int ret;
396 
397 	pci_read_config_dword(f4, REG_PROCESSOR_TDP, &val);
398 	data->base_tdp = val >> 16;
399 	tmp = val & 0xffff;
400 
401 	pci_bus_read_config_dword(f4->bus, PCI_DEVFN(PCI_SLOT(f4->devfn), 5),
402 				  REG_TDP_LIMIT3, &val);
403 
404 	data->tdp_to_watts = ((val & 0x3ff) << 6) | ((val >> 10) & 0x3f);
405 	tmp *= data->tdp_to_watts;
406 
407 	/* result not allowed to be >= 256W */
408 	if ((tmp >> 16) >= 256)
409 		dev_warn(&f4->dev,
410 			 "Bogus value for ProcessorPwrWatts (processor_pwr_watts>=%u)\n",
411 			 (unsigned int) (tmp >> 16));
412 
413 	/* convert to microWatt */
414 	data->processor_pwr_watts = (tmp * 15625) >> 10;
415 
416 	ret = fam15h_power_init_attrs(f4, data);
417 	if (ret)
418 		return ret;
419 
420 
421 	/* CPUID Fn8000_0007:EDX[12] indicates to support accumulated power */
422 	if (!boot_cpu_has(X86_FEATURE_ACC_POWER))
423 		return 0;
424 
425 	/*
426 	 * determine the ratio of the compute unit power accumulator
427 	 * sample period to the PTSC counter period by executing CPUID
428 	 * Fn8000_0007:ECX
429 	 */
430 	data->cpu_pwr_sample_ratio = cpuid_ecx(0x80000007);
431 
432 	if (rdmsrl_safe(MSR_F15H_CU_MAX_PWR_ACCUMULATOR, &tmp)) {
433 		pr_err("Failed to read max compute unit power accumulator MSR\n");
434 		return -ENODEV;
435 	}
436 
437 	data->max_cu_acc_power = tmp;
438 
439 	/*
440 	 * Milliseconds are a reasonable interval for the measurement.
441 	 * But it shouldn't set too long here, because several seconds
442 	 * would cause the read function to hang. So set default
443 	 * interval as 10 ms.
444 	 */
445 	data->power_period = 10;
446 
447 	return read_registers(data);
448 }
449 
450 static int fam15h_power_probe(struct pci_dev *pdev,
451 			      const struct pci_device_id *id)
452 {
453 	struct fam15h_power_data *data;
454 	struct device *dev = &pdev->dev;
455 	struct device *hwmon_dev;
456 	int ret;
457 
458 	/*
459 	 * though we ignore every other northbridge, we still have to
460 	 * do the tweaking on _each_ node in MCM processors as the counters
461 	 * are working hand-in-hand
462 	 */
463 	tweak_runavg_range(pdev);
464 
465 	if (!should_load_on_this_node(pdev))
466 		return -ENODEV;
467 
468 	data = devm_kzalloc(dev, sizeof(struct fam15h_power_data), GFP_KERNEL);
469 	if (!data)
470 		return -ENOMEM;
471 
472 	ret = fam15h_power_init_data(pdev, data);
473 	if (ret)
474 		return ret;
475 
476 	data->pdev = pdev;
477 
478 	data->groups[0] = &data->group;
479 
480 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "fam15h_power",
481 							   data,
482 							   &data->groups[0]);
483 	return PTR_ERR_OR_ZERO(hwmon_dev);
484 }
485 
486 static const struct pci_device_id fam15h_power_id_table[] = {
487 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
488 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
489 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
490 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_15H_M70H_NB_F4) },
491 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
492 	{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
493 	{}
494 };
495 MODULE_DEVICE_TABLE(pci, fam15h_power_id_table);
496 
497 static struct pci_driver fam15h_power_driver = {
498 	.name = "fam15h_power",
499 	.id_table = fam15h_power_id_table,
500 	.probe = fam15h_power_probe,
501 	.resume = fam15h_power_resume,
502 };
503 
504 module_pci_driver(fam15h_power_driver);
505